Creature Mechanic: Lingering and Regenerating

Two new creature mechanics that can give a creature some staying power. Keep in mind the system has folk roll their hit dice for each encounter and typically you only lose one hit die per attack you take.

Lingering may be appropriate for ghosts, swarms, slimes, etc. Regeneration is for creatures with heavy duty supernatural healing. Use both for a nightmare creature that will make your players throttle you.

Lingering: When this creature would lose a hit die in combat, instead reroll it. If the result is a one, it loses it as usual.

Lingering Hardcore: And for a small, hydra-esque twist, if the rerolled die comes up as a certain number, like say a six, the creature also gets to roll a bonus hit die too!

Regenerating: On each of its turns, this creature rerolls a previously lost hit die unless it took damage from its vunerablities list within the last round.

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Lastly, I know my art up there kinda sucks (those are supposed to be ghostly carp up there), but in my defense I am out of practice, photographed it straight out of a moleskin, and made it without any penciling first.